Dietary Soy Supplement on Fibromyalgia Symptoms: A Randomized, Double-Blind, Placebo-Controlled, Early Phase Trial

Table 1

Summary of data analysis with a separation testa.

Outcome	Control (placebo)		Treatment (soy)		SDE	Δ/2b	Mean difference (placebo/soy)	Separation in favor of placebo or soyc	Further research with soy indicated?
	Mean change in scores	95% CI	Mean change in scores	95% CI
Intent-to-treat analysis
F1-11^d	−0.51	−3.55 to 2.54	−0.07	−1.93 to 1.79	0.18	0.15	−0.44	Placebo	No
F12^d	−2.06	−8.69 to 4.57	−1.26	−7.00 to 4.48	0.45	0.37	−0.80	Placebo	No
F13^d	−1.12	−7.01 to 4.77	−0.32	−5.08 to 4.44	0.39	0.32	−0.80	Placebo	No
F14-20^d	−8.84	−38.73 to 21.05	−6.56	−29.36 to 16.24	1.91	1.57	−2.28	Placebo	No
Total FIQ scores	−12.52	−53.34 to 28.29	−8.21	−39.39 to 22.97	2.61	2.15	−4.32	Placebo	No
Total CES-D scores	−5.12	−31.60 to 21.36	−1.92	−8.12 to 4.28	1.39	1.15	−3.20	Placebo	No
Per-protocol analysis
F1-11^d	−0.79	−4.52 to 2.94	−0.15	−2.89 to 2.59	0.32	0.27	−0.64	Placebo	No
F12^d	−3.22	−10.63 to 4.20	−2.62	−10.16 to 4.92	0.71	0.58	−0.60	Placebo	No
F13^d	−1.75	−8.89 to 5.39	−0.67	−7.63 to 6.29	0.68	0.56	−1.08	Placebo	No
F14-20^d	−13.81	−47.69 to 20.07	−13.67	−40.64 to 13.30	2.95	2.42	−0.15	Neither	…^e
Total FIQ scores	−19.57	−65.40 to 26.26	−17.10	−55.62 to 21.42	4.06	3.34	−2.47	Neither	…
Total CES-D scores	−8.00	−40.05 to 24.05	−4.00	−10.99 to 2.99	2.37	1.95	−4.00	Placebo	No

aAs described by Aickin [18, 19]; bΔ/2 = 1.645*SDE/2; cIf the mean difference exceeds Δ/2 (in the favorable direction, positive for soy), further research is recommended; dF1-11, questions 1-11 of FIQ, which rate the ability to complete various activities and are scored and summed to yield 1 physical impairment score (0, no impairment; 10, maximum impairment); F12, question 12 of FIQ, which inquires about the number of days out of the past 7 days when the patient felt well (0, no impairment; 10, maximum impairment); F13, question 13 of FIQ, which inquires about the number of days during the past week when the patient missed work, including housework, because of fibromyalgia (0, no impairment; 10, maximum impairment); F14-20, questions 14-20 of FIQ, which are a series of visual analog scales for rating the various symptoms characteristic of FMS (0, no impairment; 70, maximum impairment); eEllipses indicate not enough information to make a recommendation. CI, confidence interval.